1. Field of the Invention
The present invention relates to tools for removing the spinal cord from carcasses.
2. Description of Related Art
Spinal cord removal tools are used in the processing of carcasses to remove the spinal cord from the spinal cord channel surrounding it. Such tools may also be referred to as xe2x80x9cspinal cord grindersxe2x80x9d due to the difficulty of removing the spinal cord completely from the bony channel surrounding it, which has many irregularities and protrusions. A related problem is the elongated spinal cord membrane, which tends to wrap around the shaft of motorized removal tools and interfere with operation of the tool and proper removal of the spinal cord.
One tool that addresses these problems in removing the spinal cord is seen in European Patent EP 0 890 313 B1, which uses a motor driven blade disk spinning inside a housing. The blade disk includes multiple spinal cord removal blades oriented perpendicular to the plane of the disk. The removal blades are spaced around the perimeter of the blade disk and project out from the housing on the working side as the disk spins. Each removal blade includes a front cutting edge, a left cutting edge and a right cutting edge.
The front cutting edges are rounded and project outward from the perimeter of the blade disk that supports them. The shape of the removal blades allows them to penetrate into the spinal cord channel to scrape and cut out the spinal cord as the blade disk spins. The operator guides the exposed perimeter of the spinning blade disk, with the protruding removal blades, into the spinal cord channel.
The side cutting edges on the removal blades cooperate with fixed side blades mounted on left and right sides of the housing to cut up the spinal cord membrane as it is brought into the tool. The fixed side blades are mounted at an angle to the spinning side edges of the removal blades and provide a scissors-like cut to shear the spinal cord membrane and cut it into smaller pieces. A vacuum opening is located inside the tool near the side blades to remove the waste material.
One difficulty with the tool shown in EP 0 890 313 B1 is the fixed location of the side blades relative to the side edges of the removal blades. As the blades wear, a gap quickly develops between these blades and the shearing action becomes intermittent. When the side blades fail to shear the spinal cord membrane, it wraps onto the shaft of the tool. The tool must then be disassembled and cleaned and new blades must be installed. The initial shaping of the blades by grinding is also very difficult in this design in view of the manner in which the side blades are non-adjustably mounted with a fixed spacing between them.
Bearing in mind the problems and deficiencies of the prior art, it is therefore an object of the present invention to provide a spinal cord removal tool that operates for longer than prior art tools before requiring cleaning or adjustment.
It is another object of the present invention to provide a spinal cord removal tool with self-adjusting side blades.
Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.
The above and other objects, which will be apparent to those skilled in art, are achieved in the present invention, which is directed to a spinal cord removal tool for removing a spinal cord and spinal cord membrane from a carcass. The tool includes a motor, a housing, and a blade disk mounted in the housing. Multiple spinal cord removal blades are mounted around the perimeter of the blade disk, each removal blade having a front cutting edge, a left cutting edge and a right cutting edge. The motor spins the blade disk within the housing and a portion of the blade disk, is exposed on a working side of the tool.
The operator aligns the plane of the spinning blade disk with the spinal cord channel and brings the working side into contact with the spinal cord channel to begin the removal process. The shape of the removal blades allows them to enter the channel and remove the spinal cord and spinal cord membrane.
The blade disk spins between a left side blade and a right side blade. The side blades are mounted on the housing for motion towards and away from the left and right cutting edges of the spinal cord removal blades. A left side spring pushes the left side blade in towards the left cutting edges of the spinning spinal cord removal blades. A right side spring pushes the right side blade in towards the right cutting edges of the spinal cord removal blades. The floating spring mounting of the side blades makes them self-adjusting and ensures that they always remain in cutting contact with the side edges of the spinning removal blades.